Summer to Fall in the Isles (Credit: Meteorologist Jessica Olsen)

Haleiwa, HI: Image Courtesy: Meteorologist Jessica Olsen

DISCUSSION: Autumn officially began September 22nd and ends on December 21st 2018 in the Northern Hemisphere. Fall marks the transition from summer to winter, a time when many changes are evident in the Northern Hemisphere.

Some of these transitions include:

• Decrease in duration of daylight
• Decrease in temperature
• Falling/changing of leaf color
• Harvesting of crops

However some of these transformations aren’t always apparent in the Northern Hemisphere as other locations, take for example the 50th state, Hawaii. Hawaii does not observe daylight saving time, despite this there is a decrease in duration of daylight, making early morning commutes and evening commutes more challenging as drivers are now back to using headlights. The amount of daylight observed is dependent on several factors: latitude and Earths orbit around the sun, as the Earth’s axis is tilted, the orientation to the sun is always changing throughout the year, thus a change in distribution of sunlight on the Earth’s surface as a specific latitude. Timeanddate.com is a simple site designed to provide information on sunrise, sunset and day length based on location. For example if we input Honolulu, HI on October 18th 2018, Sunrise is 6:28am and Sunset at 6:04pm, providing approximately 11:36 of daylight. Whereas New York, NY, experiences a sunrise at 7:10am and sunset at 6:10pm for a total daylight of 11:01.
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In addition to differences in daylight and times observed for such, temperatures trend on the decreased side of the spectrum as tilt moves away from the sun in the Northern Hemisphere. This has seemingly brought early snows to places like Wichita KS, Woodstock VT, and even Cortland (Central) NY! This is a time where fall foliage is peak in upstate New York, central Colorado and parts of northern Wisconsin. As we near mid-November more than half of CONUS is past peak, experiencing cooler weather despite the possibilities for tropical development near the Lesser Antilles, as we still are reminded it is still hurricane season in the Atlantic until the 30th.


Crop harvesting is apparent for nearly every state in the U.S. Some often fall harvest vegetables are beets, beans, turnips, green onions and of course apples and pumpkins. These being heavily popular among families looking for great activities during the fall transition period.  Hawaii seeing some different harvests as the fall season is well underway, such as various avocados 9often available different times of the year), apple bananas, cabbage and carrots often harvested year-round, limes, oranges an so much more. With Hawaii home to nearly 11 of the 13 climate zones in the world, it is a great environment to grow a variety of fruits and vegetables and use a great deal of these seasonally to supplement any meal!


Lastly, the transition of summer to fall signals the time for advanced surfers to pull out the boards for big-wave surf. During this seasonal progression, winds can increase, humidity decrease with an increase in swell height. Often we see the swell increase on north and west facing shores throughout the island chain, marking a time for World Surf League events such as the Vans Triple Crown, Beachwaver Maui Pro, Billabong Pipe Masters and more! Autumn is a great season to see some of these changes occur despite the lack of foliage change in Hawaii. It is an opportune time to view many big-wave events, try seasonal fruits and vegetables, and maybe spot a stray whale coming in for the winter season.


For information on fall changes in Hawaii or CONUS visit the Global Weather and Climate Center!

© 2018 Meteorologist Jessica Olsen